William a



(No Model.)

W. A. PHILLIPS. PENCIL SHARPENER.

No. 479,658. Patented July 26, 1892.

awwwbo'z 3 1011519 s UNITED STATES PATENT OFFICE.

WILLIAM A. PHILLIPS, OF THE UNITED STATES ARMY.

PENClL-SHARPENER.

SPECIFICATION forming part of Letters Patent No. 479,658, dated July 26,1892.

Application filed April 8,1892- Serial No. 428,349. (No model.)

T0 at whom, it WLOI/y concern:

Be it known that I, WILLIAM A. PHILLIPS, alieutenant of the UnitedStates Army, a citizen of the United States, and now residing at FortKeogh,inthecountyof OusterandState of Montana, have invented certain newand useful Improvements in Pencil-Sharpeners; and I do hereby declarethe following to be afull, clear, and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

My invention relates to an improved pencil-sharpener, more particularlyfor slate-pencils, and is adapted to be applied to a slateframe or, asfor that matter, to a school-desk; and it has for its object to producea taper upon the pencil clear to the point in sharpening the same and toprevent clogging or breaking oft the point; and to these ends theinvention consists in the detailed construction and arrangement of theparts, substantially as hereinafter more fully disclosed, and pointedout in the claims.

In the accompanying drawings, Figure 1 is a view showing my inventionapplied to a slate-frame, parts being broken away. Fig. 2 is a detachedperspective view of my invention. Fig. 3 is a plan view thereof. Fig. 4is an inverted view. Fig. 5 is a lougitudinalsection of the same.

In the embodiment of my invention I provide a conical externally screwthreaded metal receptacle or chamber A, adapted, therefore, to beapplied to or screwed into a correspondingly-shaped somewhat-less-sizedopening ina slate-frame or to a school-desk. To aid in effecting this,the flared or flanged end of the chamber or receptacle A has producedtherein transverse screw threaded grooves a, a, to permit the readyapplication thereto of the point of a screw-driver for screwing ordriving the chamber or receptacle into the slate-frame or desk.

The chamber or receptacle A has arranged therein a series of triangularpyramid-shaped cutters or blades 13, vanishing at their upper taperingends at the upper inner edge of said receptacle or chamber, whiletheirlower ends converge toward but do not touch each other,

thus providing for the projection of the pointof the pencil below saidcutters or blades to prevent the breaking off said point.

The maximum cross-sectional area of the cutters or blades B does notoccupy the exclusive bottom area of the chamber A, openings b I) beingprovided thereat for the escape of the pencil-dust produced insharpening the pencil, thus preventing the clogging of the blades orcutters and the chamber. The pyramid shaped or triangular cutters oblades as they wear away are thus self-sharpening, the advantages ofwhich are obvious.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is-

1. The pencil-sharpener consisting of the conicalexternally-screw-threaded chamber or receptacle having internalpyramid-shaped cutters or blades, substantially as and for the purposesset forth.

2. The pencil-sharpener consisting of the conicalexternallyscrew-threaded chamber or receptacle having its flared orflanged end provided with screw-threaded grooves, said chamber orreceptacle having internal pyramid-shaped cutters or blades,substantially as set forth.

In testimony whereof I affix my signature in presence of two Witnesses.

WILLIAM A. PHILLIPS.

Witnesses:

G. H. LANCE, JoIIN GREEN BALLANOE.

